We use programs as organizational tool for projects. (Think of Portfolio as the file cabinet in the corner, Programs are the drawers, project is the folder, and documents/tasks/issues are the documents in the file)
Almost all of our business units use Portfolio for the brand and then the programs for key initiatives based on the Annual SOW. (Example: Company is Novartis, Portfolio is Gilenya, Programs are 2016 Digital Campaigns and 2016 Direct Mail). That way at the end of the year, I can build a report that kind of matches the Annual SOW and they can compare the reasons.